SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fb5b7f98761647639408d34b5299e784174d5cf635317fa5965bb3318b668b4' 
  AND token = 'EojS4Cg9jInNnCBWA3VHEPp4HQvQt9xchq7JGrYr3lQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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