SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0661a8abec12a14fd6a71e82aa4b320c1e2a51ac95d55f0000458a0bdafbfd0' 
  AND token = 'HkZOpSRCv375FD4jMhCrargEe7c64RM2tIuVvZp6ZGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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