SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16436eae15ae51ffd8ee75e0b936fab91b7c2eb398ae42089b801ff3c8568ba7' 
  AND token = 'OggbvZtTO5T3CJFr/Oyf9HDgBxmv2zHXEuMoIIaoP9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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