SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70babefbde5ace1e1d1ba07316fd8d7eaa34cf10d2c208253a7bb4d8e2b7d453' 
  AND token = 'bpOPDcOexjny3IOSNlBGAPIYellJbaX4SgQqhourRpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}