SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e32e8bde040ba770cd4eeb7504f2f378f08a05782a1baed23b6da05c83eacbe' 
  AND token = 'PbD73lbYQ6RTyLdlIEFFBsl9ibEYryI1w07uC1HEKaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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