SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e84c4a73c75f7ee90c429060a25e796a724fd7e3426d2997270376ab7d45b205' 
  AND token = 'u1tkfjz7sFSVeHdxxtCir/HXVntSm8vGz1tI1sBwelk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}