SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da58f59e339312dcd567855200bdd7fa83717b7a7f9e40115520163865815105' 
  AND token = '+Spa1EXhdwoPffo3oXCpNYPDgbZpx8s4EpCIjhyvkio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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