SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4eab3e1585cf1063ec9b1958a8bee2cbce95f0b8453bdd1f8d5278a73d627faf' 
  AND token = 'HKnPiZsCkAOzbatDDIiAjZZol+9GhwV3r57L50pJ7Qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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