SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a2ba7fdbb177bb7dec9a163b84c2debf0b5a660bb6c0e35e93145c1918d90d73' 
  AND token = 'HtgY3NA0z/JDFv4GgYK/Y7cg122ekCOmk0urQKZNUw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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