SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cdd1e85b816fb3fcfe5e0cd92f8aa00814c5cee677ffa81fd5b3894d465429bd' 
  AND token = 'PwfPqrp7hpKOCpHumlKL8i5qYecffrCsnu+DkLjtWTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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