SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a1afb555d3d3741fdec5dc7d424abefdf744dbb3f4c88b667263c3a12f0f439' 
  AND token = 's/Fin/XnLbU2GFU4EOjF7STFaYOvQjoR3DUdGYW2jYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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