SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '676507096d0dc1126bae29bba9d429ce74ee0249df467ce1978d19ad6c586405' 
  AND token = 'yTjKXXHmecbaiRDF6Bfn2oVImyP8K4RHxA6rK9SL4YQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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